The present invention relates to a thermal fixing device for an image recording apparatus in which an image formed on a sheet is thermally fixed on the sheet.
In a conventional copying machine, in the case where a latent image formed on a photo-sensitive, pressure-sensitive sheet is developed and transferred to a developer sheet to provide a visible image, the photo-sensitive, pressure-sensitive sheet and the developer sheet are superimposed one on the other and pressure is applied thereto. Thereafter, the developer sheet is blown by a heated air stream with a dryer type heating unit to thereby thermally fix the image thereon and accelerate coloring of the image while traveling the developer sheet.
However, in this case, when the developer material coated on the developer sheet is heated, a gas having an unplesant smell is generated from the developer sheet. The conventional apparatus is designed so that the gas is not diffused out of the apparatus.